CN111495121A

CN111495121A - On-site manufacturing, installing and constructing process of absorption tower of desulfurization and denitrification device

Info

Publication number: CN111495121A
Application number: CN202010332473.7A
Authority: CN
Inventors: 周力
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-04-24
Filing date: 2020-04-24
Publication date: 2020-08-07

Abstract

The invention discloses a construction process for on-site manufacturing, mounting and constructing an absorption tower of a desulfurization and denitrification device, which relates to the technical field of chemical industry and comprises the following steps: carrying out material inspection; arranging plates; rolling and prefabricating; performing foundation acceptance (which can be performed synchronously with the construction of the procedures S1, S2 and S3); mounting a ring plate and laying a bottom plate; assembling the vertebral body; assembling a first ring plate under the vertebral body; sequentially installing other rings of wall plates, synchronously welding the inner and outer supporting pieces and the connecting pipe of the tower; and manufacturing a 40.5m steel structure tower (which can be synchronously constructed with the processes of S1, S2 and S3). The process for manufacturing, installing and constructing the absorption tower of the desulfurization and denitrification device on site has the advantages that the lower barrel of the desulfurization tower is constructed by adopting a flip-chip method, the cone and the upper barrel are constructed by adopting a normal installation method, the construction period is shortened, the tower body is made of stainless steel, the electro-gas welding technology is adopted, the construction quality is ensured, the thickness of the barrel wall of the tower body is thin, and the inner part is supported during construction to prevent welding deformation.

Description

On-site manufacturing, installing and constructing process of absorption tower of desulfurization and denitrification device

Technical Field

The invention relates to the technical field of chemical industry, in particular to a construction process for on-site manufacturing, installing and constructing an absorption tower of a desulfurization and denitrification device.

Background

Along with the severe situation of atmospheric pollution, the national requirements on SOX and NOX emission are increasingly strict, the environmental protection law is newly implemented in 1 month and 1 month in 2015, the emission standard requirements are improved, the penalty on environmental illegal behaviors is increased, the new emission standard requirements are met, the emission concentration of SO2 in key areas and newly-built oil refineries is less than 50mg/Nm3, the emission concentration of NOX is less than 100mg/Nm3, SOX and NOX concentrations in many fields such as process coal for thermal power units, coal-fired industrial boilers and industrial systems, civil life coal and the like are seriously over-standard, therefore, a large number of desulfurization and denitration devices are newly built in China in the next years, all the time, the flue gas desulfurization devices in China depend on foreign technologies and equipment, and the calcium desulfurization is taken as the main reason, namely, the desulfurizer of the calcium method is rich in limestone and cheap, and the calcium method technology is quite mature and open abroad, the method is easy to obtain, but after the introduced calcium desulphurization technology is used for more than ten years in China, the biggest defect is gradually shown, namely, the problem of secondary pollution which is difficult to solve is caused by the massive stacking of desulphurization product gypsum, and in addition, the technology also has the problems of large investment, high energy consumption, easy scaling and blockage of a system, high operating cost and the like.

With the increasingly prominent technical defects of the calcium method, the GE, Lurgingnergie and Perilla frutescens in the United states begin to research more advanced ammonia desulphurization technology, and has entered into a large-scale application stage, the ammonia desulphurization technology becomes the leading technology in the world at present, and at present, more than one industrial enterprises in China adopt the ammonia desulphurization technology for removing sulfur dioxide, wherein about 60 percent of the devices are put into operation, the absorption tower is used as the core equipment in the ammonia desulphurization device and is the heaviest in the whole flue gas desulphurization device, the selection of the installation scheme has obvious influence on the installation cost and the installation period, and the absorption tower needs to be prefabricated and processed on the construction site, therefore, a construction site needs to be reasonably arranged, the construction and installation method of the existing absorption tower is complex, the construction time is long, the construction quality is poor, and a large amount of manpower is consumed, so that the construction process for the on-site manufacturing and installation of the absorption tower of the desulfurization and denitrification device is provided to solve the problems.

Disclosure of Invention

The invention aims to make up the defects of the prior art, and provides a construction process for manufacturing and installing an absorption tower of a desulfurization and denitrification device on site.

In order to solve the technical problems, the invention provides the following technical scheme: a construction process for on-site manufacturing, installing and constructing an absorption tower of a desulfurization and denitrification device comprises the following steps: carrying out material inspection; arranging plates; rolling and prefabricating; performing foundation acceptance (which can be performed synchronously with the construction of the procedures S1, S2 and S3); mounting a ring plate and laying a bottom plate; assembling the vertebral body; assembling a first ring plate under the vertebral body; sequentially installing other rings of wall plates, synchronously welding the inner and outer supporting pieces and the connecting pipe of the tower; manufacturing a 40.5m steel structure tower (which can be synchronously constructed with the procedures of S1, S2 and S3); performing lifting point reinforcement and lifting appliance setting by a flip-chip method (after the step S9 is finished); prefabricating an upper tower (after the construction of the step S10 is finished); hoisting the upper tower (after the construction of the steps S11 and S8); erecting a group of platforms (which can be synchronous with the construction of the working procedures); manufacturing the upper cylinder in a segmented manner (after the construction of the step S13 is finished); hoisting the upper barrel in sections; carrying out supporting point construction; carrying out water holding leakage test; mounting an internal part; and (5) handing over and organizing completion and acceptance.

Furthermore, the materials are checked and accepted, the main materials of the equipment are all 316L materials, normal large and medium-sized enterprises are selected for controlling the quality of raw materials and the delivery channels, the materials are checked according to corresponding material check standards, products can be delivered only after being checked to be qualified by production plant inspection departments and accompanied with a qualification certificate, strict materials are checked in the field, each batch of materials are checked to be delivered with the qualification certificate and the test report, the chemical components and the mechanical properties of various steel products are tested again according to specified sampling, the equipment can be used after being qualified, the butt joint below 13m of the tower body needs to be subjected to local ultrasonic detection, the detection length is not less than 20% of the length of each welding seam, and not less than 250mm, the butt joint above 13m needs to be subjected to local ultrasonic detection, and the detection length is not less than 10% of the length of each welding seam, and not less than 250 mm.

Further, the foundation is checked and accepted before the bottom plate is laid, and the installation work can be started after the position, the size and the elevation of the foundation are checked and found out again.

Further, the ring plate installation and the bottom plate laying are carried out, before the tower body construction of the absorption tower, the steel structure tower frame is constructed to the height of 40.5m, so that a lifting point is conveniently set, the stability of the tower body is conveniently kept when the tower body is inverted, the plate arrangement, blanking, plate rolling, smoke gas inlet, upper tower frame, upper cylinder body prefabrication and the like of lower cylinder bodies can be carried out in an equipment prefabrication site while the tower frame construction is carried out, after the tower frame is constructed to the elevation of 40.5m, the bottom plate laying work can be carried out, the bottom plate is a butt welding line, the plate arrangement size, the length tolerance of-2 mm, the width tolerance of-2 mm and the difference of diagonal lines are less than or equal to 3.0mm when the tower frame is prefabricated, the diameter deviation of a center circle of a bolt hole of a basic ring plate and the chord length deviation of two adjacent holes and any two holes are 2mm, the total flatness deviation of the bottom, to control the deformation, a suitable weight must be added to the bottom plate to bring it into full contact with the concrete foundation until the welding is completed and after a suitable time, the temporary weight of the bottom plate can be removed.

Further, cone assembling, tower body blanking and cutting are carried out according to a plate arrangement diagram, mark transplanting and size checking records are made before blanking and cutting, checking is carried out according to a construction diagram, checking is carried out correctly, the blanking length tolerance of a plate is +/-1 mm, the width tolerance of +/-1 mm and the diagonal tolerance of +/-2 mm, the plate arrangement diagram is drawn before cone prefabrication, a 1:1 large sample and a large sample diagram of each sector plate are placed on a steel plate according to the drawing size, the size of each sector plate is determined, cone prefabrication is carried out according to the size of the large sample diagram, single cone plates are spliced on the plate arrangement diagram, splicing is carried out in butt joint, splicing forming is carried out on an assembling platform during butt joint, double-side welding is adopted, welding is carried out flatly, and inner welding lines are ground flatly.

Further, prefabricating an upper tower, assembling the whole tower body to facilitate the access and ventilation of constructors and equipment, manufacturing a buttress by using a phi 325 × 8 steel pipe, wherein the height of the buttress is 450mm, the buttress is uniformly distributed every 1m along the circumference, the upper part and the lower part of the buttress are welded by using 316L and 10mm steel plates 350 × 350, the lower steel plate is fixed with a tower bottom plate section, the horizontal error of the upper surface of the buttress is not more than 2mm, a mounting circumferential line is marked on the upper surface of the buttress, a limit baffle is arranged, after the cone and the first circle of wall plate under the cone are mounted, 4 temporary lifting lugs are arranged at the position 500mm below a corner welding line of the wall plate and the cone, the wall plate is reinforced by using 316L and 10mm steel plates, the inside of the buttress is supported by using a phi 76 5 carbon steel pipe in a cross shape, 316L backing plates are additionally arranged at the connecting position of the steel pipe and the wall plate, all welding lines of the lifting lugs must be subjected to 100% nondestructive testing, the qualified testing can be used, and the tower lifting points are arranged on the tower column at the height of 40.0 m.

Further, carry out upper portion pylon hoist and mount, the flip-chip method is adopted to the following part of absorption tower cone, utilizes the pylon to set up electric block and carries out the flip-chip to the barrel, the prefabricated and segmentation hoist and mount of the above part segmentation of cone, be convenient for keep the tower body stable when the tower body flip-chip simultaneously, the lower part tower body adopts the flip-chip method, will do the support during the construction, prevent hoist and mount in-process tower body unstability, cone section and roof tower body adopt the construction of just-installing method, during the construction, will do the work of taking of scaffold frame and tear open, ensure construction safety.

Further, the upper barrel is manufactured in a segmented mode, prefabrication of the upper barrel is carried out on the assembly platform and is carried out in two segments, the upper segment is 18m, the lower segment is 21m, barrel connecting pipes, supporting points and the like are installed synchronously in the prefabrication process, the specification and the size of a plate must be checked before rounding, the direction of a groove is noticed during rounding, wall plates are numbered after rolling forming inspection is qualified, and the difference between the maximum diameter and the minimum diameter of the barrel on the same section is not more than 25 mm.

Further, the upper barrel is hoisted in a segmented mode, the maximum hoisting height of the upper barrel during hoisting is about 95m, the hoisting load is about 7.4t, the turning radius is about 18m, and a 300t truck crane is planned to be selected.

Furthermore, the acceptance of the delivery and the organization is carried out according to NB/T47041-2014 Tower container, the welding quality of the welding seam of the tower body must meet the requirement of an assembly drawing, nondestructive testing shall meet the regulation in JB/T4730-2005, wherein the ultrasonic testing level II is qualified, the penetration testing level I is qualified, the straightness tolerance of the tower body is 25mm, the straightness deviation of any 3000mm long cylinder section is not more than 3mm, the perpendicularity tolerance is 30mm, the ovality of the upper cylinder body is not more than 10mm, and the perimeter deviation of the outer diameter is not more than 6 mm.

Drawings

FIG. 1 is a flow chart of the construction process of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1, the invention provides a technical scheme that the construction process for on-site manufacturing and installation of the absorption tower of the desulfurization and denitrification device comprises the steps of S1, material inspection, 316L material as the main material of the equipment, selection of regular large and medium enterprises for raw material quality control and material inlet channels, factory inspection of the materials according to corresponding material inspection standards, factory delivery of products after being inspected to be qualified by a factory inspection department and accompanied by a qualification certificate, strict material in-field inspection, adherence to each batch of material inspection factory qualification certificate and test report, re-inspection of chemical components and mechanical properties of various steel products according to a specified sampling, use after qualification, local ultrasonic inspection of a butt joint below 13m of a tower body, plate arrangement and plate prefabrication S2, and plate arrangement and plate prefabrication of S3.

S4, checking and accepting the foundation (which can be synchronously performed with the construction of the working procedures S1, S2 and S3), checking and accepting the foundation before the bottom plate is paved, and starting installation work after the position, the size and the elevation of the foundation are checked to be correct;

s5, installing ring plates, laying bottom plates, before constructing the tower body of the absorption tower, constructing a steel structure tower frame to a height of 40.5m to set a lifting point, and simultaneously keeping the tower body stable when the tower body is inverted, wherein the steel structure tower frame can be prefabricated with plate arrangement, blanking, plate rolling, a smoke inlet, an upper tower frame, an upper cylinder body and the like of a lower cylinder body in an equipment prefabrication site, after the tower frame is constructed to the height of 40.5m, the bottom plate can be laid, the bottom plate is a butt welding line, the plate arrangement size, the length tolerance of-2 mm, the width tolerance of-2 mm, the difference of diagonal lines is less than or equal to 3.0mm, the central circle diameter deviation and the adjacent two holes and the random two hole chord length deviation of the base plate are 2mm, the total planeness deviation of the bottom plate is not more than 5mm, and before the bottom plate is arranged and welded in blocks, in order to control deformation, the floor must be weighted appropriately to bring it into full contact with the concrete foundation until the weld is complete and after a suitable time, the temporary weight of the floor can be removed.

S6, carrying out cone assembly, wherein blanking and cutting of the tower body are carried out according to a plate arrangement diagram, before blanking and cutting, marking, transplanting and size inspection records are carried out, checking is carried out according to a construction diagram, the checking is correct, the blanking length tolerance of a plate is +/-1 mm, the width tolerance of the plate is +/-1 mm, and the diagonal tolerance of the plate is +/-2 mm, the plate arrangement diagram is drawn before cone prefabrication, a 1:1 large sample and a large sample diagram of each sector plate are placed on a steel plate according to the drawing size, the size of each sector plate is determined, cone prefabrication is carried out according to the size of the large sample diagram, single cone plates are spliced according to the plate arrangement diagram, splicing and butt joint are adopted, during butt joint, splicing and forming are carried out on an assembly platform, double-side welding is adopted, welding is carried out flatly, and inner welding lines are;

s7, assembling a first ring plate under the vertebral body; s8, sequentially installing the rest circles of wall plates, synchronously welding the inner and outer supporting pieces and the connecting pipes of the tower; s9, manufacturing a 40.5m steel structure tower (which can be synchronously constructed with the procedures of S1, S2 and S3); s10 is performed to reinforce the hoisting point by the flip-chip method and set the spreader (performed after the step S9 is completed).

S11 prefabricating the upper tower (after S10 process construction is finished), assembling the whole tower body to facilitate the entering and exiting and ventilation of constructors and equipment, manufacturing buttresses by steel pipes of phi 325 × 8, wherein the buttresses are 450mm in height and are uniformly distributed every 1m along the circumference, welding the upper and lower ends of the buttresses by 316L and 10mm steel plates 350 × 350, fixing the lower steel plates to the tower bottom plate section, ensuring that the horizontal error of the upper surfaces of the buttresses is not more than 2mm, marking out and installing circumferential lines on the upper surfaces, arranging limiting baffles, arranging 4 temporary lifting lugs at positions 500mm below corner welding lines of the wall plates and the cone after the cone and the first circle of wall plates under the cone are installed, reinforcing the wall plates by 316L and 10mm steel plates outside the wall plates, using phi 76 x 5 carbon steel pipes as cross supports inside the wall, adding 316L cushion plates at the joints of the steel pipes and the wall plates, performing 100% nondestructive detection on all welding lines of the lifting lugs, using the qualified tower lifting points, and arranging the tower lifting points on the tower column at the height of 40.0 m.

S12, hoisting an upper tower (after S11 and S8 procedures are finished), arranging an electric hoist on the lower part of a cone of the absorption tower by using a flip-chip method, and inversely installing a cylinder by using the tower, prefabricating and hoisting the upper part of the cone in sections, and conveniently keeping the tower stable when the tower is inversely installed; and S13, erecting the assembly platform (which can be synchronous with the construction of the above procedures).

S14, manufacturing the upper barrel in sections (after the construction of the S13 process is finished), prefabricating the upper barrel on a pairing platform, prefabricating the upper barrel in two sections, wherein the upper section is 18m, the lower section is 21m, the barrel connecting pipe, the supporting points and the like are synchronously installed in the prefabricating process, the specification and the size of the plate must be checked before rounding, the direction of the groove is noticed during rounding, wall plate numbering is carried out after rolling forming inspection is qualified, and the difference between the maximum diameter and the minimum diameter of the barrel on the same section is not more than 25 mm.

S15, hoisting the upper barrel in sections, wherein the maximum hoisting height of the upper barrel during hoisting is about 95m, the hoisting load is about 7.4t, the turning radius is about 18m, and a 300t truck crane is selected, because the wall plate of the upper barrel is thin and high, the hoisting of the barrel must be carried out after the hoisting of the upper tower frame is finished, the barrel is hoisted one by one during the hoisting, the hoisting is stopped after the lower opening of the wall plate is lifted to about 100mm away from the bottom plate each time, and the tower frame hoisting point, the lifting lug, the rigging, the hoisting hook head and the like are inspected for 10 minutes, and then the barrel can be continuously hoisted, when the hoisting height is close to the height of the band plate, the hoisting speed is reduced, the level of the tower body is strictly controlled, and when the tower body is hoisted to the height of the lower band plate; s16, carrying out supporting point construction; s17, carrying out water holding and leakage testing; s18 performing the trim installation.

And S19 acceptance and organization completion acceptance check, wherein the acceptance check is carried out according to NB/T47041-2014 Tower container, the welding quality of the welding seam of the tower body must meet the requirement of an assembly drawing, nondestructive testing shall meet the regulation in JB/T4730-2005, the ultrasonic testing grade II is qualified, the penetration testing grade I is qualified, the straightness tolerance of the tower body is 25mm, the straightness deviation of any 3000mm long cylinder section is not more than 3mm, the perpendicularity tolerance is 30mm, the ovality of the upper cylinder body is not more than 10mm, and the perimeter deviation of the outer diameter is not more than 6 mm.

In the description of the present invention, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising a reference structure" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element. It is noted that, herein, relational terms such as "first," "second," and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. The utility model provides a construction technology is installed in on-spot preparation of SOx/NOx control device absorption tower which characterized in that includes:

s1, carrying out material inspection;

s2, carrying out plate arrangement;

s3, rolling and prefabricating;

s4, performing basic acceptance (which can be performed synchronously with the construction of the procedures S1, S2 and S3);

s5, mounting a ring plate and paving a bottom plate;

s6, vertebral body assembly is carried out;

s7, assembling a first ring plate under the vertebral body;

s8, sequentially installing the rest circles of wall plates, synchronously welding the inner and outer supporting pieces and the connecting pipes of the tower;

s9, manufacturing a 40.5m steel structure tower (which can be synchronously constructed with the procedures of S1, S2 and S3);

s10, reinforcing the hoisting point by a flip-chip method and setting a hoisting tool (after the step S9 is finished);

s11, prefabricating an upper tower (after the construction of the S10 process is finished);

s12, hoisting the upper tower (after the construction of the S11 and S8 procedures is finished);

s13, erecting a group on the platform (which can be synchronous with the construction of the above procedures);

s14, manufacturing the upper cylinder in sections (after the construction of the S13 process is finished);

s15, hoisting the upper barrel in sections;

s16, carrying out supporting point construction;

s17, carrying out water containing leakage test;

s18, mounting the internal parts;

and S19, handing over and organizing to complete and accept.

2. The process of claim 1, wherein S1 is performed to check the materials, the main materials of the equipment are all 316L materials, the raw material quality is controlled, the regular large and medium enterprises are selected as the material feeding channels, the materials are tested according to the corresponding material test standards, the products are inspected to be qualified by the factory inspection departments and can be delivered with the qualification certificate, the materials are strictly inspected in the field, each batch of material is adhered to the qualification certificate and the test report, the chemical compositions and the mechanical properties of various steel materials are tested again according to the specified sampling, the steel can be used after being qualified, the butt joint below 13m of the tower body is subjected to local ultrasonic testing, the testing length is not less than 20% of the length of each welding seam and not less than 250mm, the butt joint above 13m is subjected to local ultrasonic testing, and the testing length is not less than 10% of the length of each welding seam and not less than 250 mm.

3. The process for on-site manufacturing, installing and constructing the absorption tower of the desulfurization and denitrification device according to claim 1, which is characterized in that: s4 checks and accepts the foundation, before the bottom plate is laid, the foundation should be checked and accepted, and the installation work can be started after the position, the size and the elevation of the foundation are rechecked without errors.

4. The process for on-site manufacturing, installing and constructing the absorption tower of the desulfurization and denitrification device according to claim 1, which is characterized in that: s5, installing a ring plate and laying a bottom plate, before constructing a tower body of the absorption tower, constructing a steel structure tower frame to a height of 40.5m so as to set a lifting point, and simultaneously, keeping the tower body stable when the tower body is inverted, and simultaneously, performing plate arrangement, blanking, plate rolling, a smoke inlet, prefabrication of an upper tower frame and an upper cylinder body of a lower cylinder body in an equipment prefabrication site, and the like, after constructing the tower frame to the height of 40.5m, laying the bottom plate, wherein the bottom plate is a butt welding line, the plate arrangement size, the length tolerance of-2 mm, the width tolerance of-2 mm, the difference of diagonal lines is less than or equal to 3.0mm, the diameter deviation of a central circle of a bolt hole of a basic ring plate and the deviation of two adjacent holes and any chord length of two holes are 2mm, the deviation of the total planeness of the bottom plate is not more than 5mm, and before arranging and welding the bottom plates in blocks, the floor must be weighted appropriately to bring it into full contact with the concrete foundation until the weld is complete and after a suitable time, the temporary weight of the floor can be removed.

5. The process for on-site manufacturing, installing and constructing the absorption tower of the desulfurization and denitrification device according to claim 1, which is characterized in that: the method comprises the steps of S6, carrying out cone assembly, blanking and cutting of the tower body according to a plate arrangement diagram, carrying out mark transplanting and size checking records before blanking and cutting, checking and correcting errors according to a construction diagram, determining the blanking length tolerance +/-1 mm, the width tolerance +/-1 mm and the diagonal tolerance +/-2 mm of a plate, drawing the plate arrangement diagram before cone prefabrication, putting a 1:1 large sample and a large sample diagram of each sector plate on a steel plate according to the drawing size, determining the size of each sector plate, carrying out cone prefabrication according to the size of the large sample diagram, carrying out self splicing on a single cone plate according to the plate arrangement diagram, carrying out butt joint when the single cone plate is spliced and formed on an assembly platform, carrying out double-side welding, flattening after welding, and grinding an inner welding line.

6. The process of claim 1, wherein the upper tower is prefabricated in S11, the whole tower body is assembled to facilitate the entry and exit and ventilation of constructors and equipment, buttress piers are manufactured by steel pipes with the diameter of 325 × 8, the height of each buttress pier is 450mm, the buttress piers are uniformly distributed at every 1m along the circumference, the upper portion and the lower portion of each buttress pier are welded by 316L and a steel plate 350 × 350 with the diameter of 10mm, the lower portion of each buttress steel plate is fixed with a tower bottom plate section, the horizontal error of the upper surface of each buttress pier is not more than 2mm, a mounting circumferential line is marked on the upper surface of each buttress pier, a limit baffle is arranged, after the cone and the first ring of wall plate under the cone are mounted, 4 temporary lifting lugs are arranged at the position 500mm below the corner welding line of the wall plate and the cone, the outer portion of the wall plate is reinforced by 316L and a steel plate with the diameter of 10mm, the inner portion of each buttress steel pipe is supported by a carbon steel pipe with the diameter of 76, 316L is additionally arranged at the connecting position of the wall plate, all backing plates must be subjected to 100% nondestructive testing and qualified 316, the tower crane welding line is used after the tower crane welding line is welded at the tower, 100.

7. The process for on-site manufacturing, installing and constructing the absorption tower of the desulfurization and denitrification device according to claim 1, which is characterized in that: s12 carries out upper portion pylon hoist and mount, the flip-chip method is adopted to absorption tower cone below part, utilize the pylon to set up electric block and carry out the flip-chip to the barrel, the prefabricated and segmentation hoist and mount of above part segmentation of cone, be convenient for keep the tower body stable when the tower body flip-chip simultaneously, the lower part tower body adopts the flip-chip method, the support will be done during the construction, prevent hoist and mount in-process tower body unstability, cone section and roof tower body adopt the construction of just-installing method, during the construction, the work of taking up and tearing down of scaffold frame will be done, ensure construction safety.

8. The process for on-site manufacturing, installing and constructing the absorption tower of the desulfurization and denitrification device according to claim 1, which is characterized in that: s14, manufacturing the upper barrel in sections, prefabricating the upper barrel on a pairing platform, prefabricating the upper barrel in two sections, wherein the upper section is 18m, the lower section is 21m, in the prefabricating process, barrel connecting pipes, supporting points and the like are required to be installed synchronously, the specification and the size of a plate must be checked before rounding, the direction of a groove is noticed during rounding, after rolling forming inspection is qualified, wall plate numbering is carried out, and the difference between the maximum diameter and the minimum diameter of the barrel on the same section is not more than 25 mm.

9. The process for on-site manufacturing, installing and constructing the absorption tower of the desulfurization and denitrification device according to claim 1, which is characterized in that: s15, the upper barrel is hoisted in a segmented mode, the maximum hoisting height of the upper barrel during hoisting is 95m, the hoisting load is 7.4t, the turning radius is 18m, and a 300t truck crane is selected, the barrel must be hoisted after the hoisting of the upper tower frame is completed because the wall plate of the upper barrel is thin and high, the barrel is hoisted one by one during hoisting, the barrel is hoisted one by one when the barrel is hoisted to the position that the lower opening of the wall plate is about 100mm away from the bottom plate each time, the hoisting is stopped, the barrel is observed for 10 minutes, the barrel can be continuously hoisted after the tower frame hoisting point, the lifting lug, the rigging, the hoisting hook head and the like are checked to be free of problems, the hoisting speed is reduced when the hoisting height is close to the height of the belt plate, the horizontal level of the tower body is strictly controlled.

10. The process for on-site manufacturing, installing and constructing the absorption tower of the desulfurization and denitrification device according to claim 1, which is characterized in that: and S19 acceptance and organization completion acceptance are carried out, acceptance is carried out according to NB/T47041-2014 Tower container, the welding quality of the welding seam of the tower body must meet the requirement of an assembly drawing, nondestructive testing is in accordance with the regulation in JB/T4730-2005, wherein the ultrasonic testing level II is qualified, the penetration testing level I is qualified, the straightness tolerance of the tower body is 25mm, the straightness deviation of any 3000mm long cylinder section is not more than 3mm, the perpendicularity tolerance is 30mm, the ovality of the upper cylinder body is not more than 10mm, and the perimeter deviation of the outer diameter is not more than 6 mm.